1. Field of the Invention
This invention relates to concrete forms, and more particularly, to lightweight metal concrete forms having a separate equipment rail spaced apart from the face of the form.
2. Description of the Prior Art
A variety of concrete forms have been provided to define the boundries of an area of plastic concrete. Gasciogne Engineering Ltd. of Keynshan, England manufactures a sectionalized metal concrete form under the trademark "Atlas." Each section of the Atlas form is joined to an adjacent section by a male/female coupling unit. A plurality of spaced apart, V-shaped brackets are secured to the exterior face of the form and include paired, horizontally oriented apertures for receiving pins which compresiely secure a vertically oriented stake to the apex of a V-shaped channel in the bracket. In an alternative embodiment of the Atlas form, the upper edge of the form face is provided with a highly precise ninety degree edge. A form having a precision ninety degree edge of this type is known in the trade as an Arris form.
Gasciogne Engineering also provides a more complex form known as a Pathfinder MK II form having an Arris form face and a spaced apart equipment rail. The equipment rail is fabricated from thirty-five pound per yard railroad rail which is securely bolted at spaced apart intervals to the upper surface of a plurality of spaced apart brackets. Vertically oriented stakes penetrate through apertures in the base of the form and are positioned in alignment with the apex of V-shaped channels in the brackets. The stakes are secured to the form by horizontally oriented rods which compressively attach the stakes to the brackets. Because of the substantial weight created by the combined heavy duty form and attached thirty-five pound per yard rail, the Pathfinder MK II form must be installed, removed and handled by a crane or other mechanized lifting device. A separate equipment rail is provided since the precision Arris form face is not intended to serve both as a highly precision form edge and as a load bearing surface for receiving potentially damaging impacts and wear from loads imposed by concrete finishing equipment.